The invention provides a flanged connection component which comprises a first annular flange plate, a second annular flange plate. The first flange plate and the second flange plate are connected through a fastening piece, are aligned relative to a central shaft, and are respectively provided with base planes which are far from each other and butt joint faces which are matched with each other. Each butt joint face comprises at least one oblique plane, and a certain angle is formed between the oblique planes and the base planes. The two flange plates can shift in the axial direction in a driven mode, so that the too small or too large pressing force due to the fact that bolts extend due to thermal expansion and difference of thickness expansion amounts of the flange plates is compensated, the purpose of effective sealing is achieved, moreover, pre-tightening force borne by the bolts can be reduced on the premise of not increasing the number of the bolts, and reliability and economy of the flanged connection component are improved.